Rear bumper



FIG. 1 is a perspective view of my new invention;

FIG. 2 is a left side view thereof, a right side view being a mirror image thereof;

FIG. 3 is a top view thereof; and,

FIG. 4 is a front view thereof.

The broken lines shown in the drawings illustrate portions of the rear bumper that form no part of the claimed design. 

CLAIM The ornamental design for a rear bumper, as shown and described. 